This invention relates to a sausage filing horn capable of detecting shards or pieces of metal in a comminuted product fed through a filing horn or tube of a product packaging machine.
Filing of rucked casing discharged from a filing horn with a comminuted product is typically effected by discharging the product through the filing horn into a casing which is released from the end of the horn in a controlled manner by a braking mechanism. The filled casing is subsequently sealed or clipped and closed in incremental links in order to provide predefined unit lengths or links of product. For example, sausage discharged through a filing horn into casing, which is sealed at one end by a clip, may be filled and sealed in unit lengths by means of a clipper mechanism which operates as the filled casing is discharged from the filing horn.
During the casing filling operation, it may be desirable to detect and sense unwanted metal particles or shards in the product and, in some fashion, shunt or discard the product contaminated by the metal particles or shards before it is discharged into casing. Standard metal detectors may be installed in a horn extension between the filing horn and the clipping apparatus at one end of the horn to identify contaminated product before the product is discharged into the casing. An apparatus capable of detecting such metal particles is available from Graseby Goring Kerr of Amherst, N.Y., as their Model 426 Pipeline Metal Detection System. When such a detector senses metal particles, the logic of the detector unit shifts a valve in the horn, for example, and diverts a contaminated portion of the product from the main filling horn or pipe into a separate collection vessel.
However, use of a metal detection system and horn extension in the manner described may not be acceptable. That is, when packaging dry sausage in casing material, product definition or appearance, especially along the surface thereof is extremely important. The product must be aesthetically pleasing. One must be able to distinguish meat from fat, particularly on the surface as well as in a cross section cut, in order to provide an appealing product. It has been determined that to maintain aesthetic or appropriate product definition, it is necessary to keep the discharge filling hom or discharge pipe as short as possible. In this manner, the product is subject to less mechanical manipulation with the result that the meat and fat portions thereof do not smear together.
Unfortunately, utilization of a metal detection system of the type described can add several feet of product transport piping to a system. This, in turn, will lead to undesirable appearance of the product, especially in dry sausage and pepperoni applications. Such an appearance is unacceptable. Thus, there has developed a need to develop apparatus and methods to solve this problem.